tree 6d54f62d39cf126c01a76f8115b60328b5f80f7e
parent e5ac812511e07c482e073fc2130641e6c9da0258
author Louis Dionne <ldionne.2@gmail.com> 1623187508 -0400
committer Copybara-Service <copybara-worker@google.com> 1654740665 -0700

[libc++] Towards a simpler extern template story in libc++

The flexibility around extern template instantiation declarations in
libc++ result in a very complicated model, especially when support for
slightly different configurations (like the debug mode or assertions
in the dylib) are taken into account. That results in unexpected bugs
like http://llvm.org/PR50534 (and there have been multiple similar
bugs in the past, notably around the debug mode).

This patch gets rid of the _LIBCPP_DISABLE_EXTERN_TEMPLATE knob, which
I don't think is fundamental. Indeed, the motivation for that knob was to
avoid taking a dependency on the library, however that can be done better
by linking against the static library instead. And in fact, some parts of
the headers will always depend on things defined in the library, which
defeats the original goal of _LIBCPP_DISABLE_EXTERN_TEMPLATE.

Differential Revision: https://reviews.llvm.org/D103960

GitOrigin-RevId: 2ae52326dab0a771b6167bc61a858389ac609ccc